1. Field of the Invention
The present invention relates to a touch screen display apparatus which easily recognizes a touch position by using an optical sensor and a method of operating the apparatus.
2. Description of the Related Art
A touch screen display apparatus in which an optical sensor is integrated with a panel, inputs information by detecting a finger image that is projected on a screen or by detecting light that is irradiated from a light emitting object such as a light pen.
Specifically, a touch screen display apparatus may derive a touch position by using external light or by using internal light emitted by the touch screen display apparatus itself. However, when the intensities of the external light and the internal light are low, such as when a black user interface (UI) is displayed while the intensity of the external light is low, a sensing operation may not be performed by an optical sensor. In addition, when the intensities of the external light and the internal light are similar to each other, an image of a touch object is not formed, and thus, the optical sensor may not perform a sensing operation. Thus, when conditions of external light and/or internal light are inappropriate, as described above, a touch position may not be recognized, thus limiting the effectiveness of the touch screen display apparatus.